A moment at old city with lover (5)
I believe the answer is:
amour
'lover' is the definition.
(I've seen this before)
'a moment at old city' is the wordplay.
'moment' becomes 'mo' (slang abbreviation. e.g. 'just a mo').
'at' is a charade indicator (letters next to each other).
'old city' becomes 'ur' (ancient city state).
'a'+'mo'+'ur'='AMOUR'
'with' is the link.
(Other definitions for amour that I've seen before include "20 [AFFAIR]" , "Love affair - loved one" , "(Secret) lover" , "Romantic liaison" , "French romance" .)